adsense analytic

Thursday, August 31, 2017

Definition of M20 grade of concrete

In construction, there should be individual strength for each building element.
To maintain the strength of concrete for different elements, various types of concrete grades are required. The strength needed for foundation, beam, slab etc. will be different.

IS 456-2000 has specified the concrete mixes into a number of grades as M10, M15, M20, M25, M30, M35 and M40. In the following construction video tutorial, brief explanation is given on M20 grade of concrete.
In M20, M denotes Mix and 20 refers to the characteristic strength (fck) of that mix i.e. 20mpa. Cement, sand and aggregates are used for mixing in the ratio of 1 : 1.5 : 3. M20 signifies mixture of cement, sand and aggregate which are prepared in such a manner that a cement concrete cube of size 15 cm x 15 cm x 15 cm is formed with characteristic strength (fck) of 20mpa while examining it after being cured for 28 days.
The characteristic strength (fck) signifies the strength under which not over 5% of test results are predictable to fail.
Cement is always calculated with weight. Commonly it is applied in terms of bags. The weight of one bag of cement is 50 kg and it contains a volume of 35 litres (or, 0.035m3). A gauge box is employed for batching of fine and coarse aggregate by volume.

To get more brief information, watch the following video tutorial.

Read more

~~~~~~~~~~~~~~~~~~~~~~
Published By
Rajib Dey
www.constructioncost.co

~~~~~~~~~~~~~~~~~~~~~~

Application of various types of plumbing pipes in construction

This construction video tutorial shows you different applications of plumbing pipes in construction.
The Plumbing system includes the entire system of pipe fittings and appliances which are utilized for water supply and drainage. In this supply and drainage system various types of pipes are employed for diverse objectives. There are two types of pipes in a plumbing system :-

1. Supply or service pipes
2. Drain pipes or waste disposal pipes
The plumbing pipes are mainly used for water supply purpose, drainage, waste disposal etc.
There are four types of pipes in supply and service pipes categories :-
1. Copper Pipes - When extreme corrosion occurs to metals due to use of ground water, then copper pipes are most suitable. In copper, there is powerful corrosive resistance capacity as compared to other pipe metals as well as substantial strength, rational ductility. The copper pipes are available in long lengths in the market. These pipes can carry high pressure and so; these pipes are also utilized for industrial purposes to undergo heavy flows. There exist two types of copper pipes like HEAVY GAUGE and LIGHT GAUGE pipes. Heavy gauge pipes are effective where pressure is extremely high. Light gauge pipes are recommended when the pressure remains under 0.15N/mm2 i.e. for internal domestic pipes.
2. Galvanized Iron Pipes - G.I pipes or steel pipes are less expensive as compared to copper pipes. But the harmful factor is that these are easily affected with corrosion in soft and acid waters. But these are very robust relating to copper pipes. Therefore, these pipes should be used in areas with less corrosion as well as in hard water areas. Hammering is required to eliminate the layers developed with hard water.
3. Polymer Piper or Plastic Pipes - Polythene pipes or plastic pipes are mostly suitable for cold water services. The plastic pipes provide various advantages which range from less corrosive, more cost effective, light weight, simple installation process, no threading needed, good resistance capacity against bacterial scale.
4. Lead Pipes - Lead pipe contains superior corrosion resistance, flexibility and hydraulic coefficient of flow. But lead content in water may result in poisoning effects which may cause harm to people. Therefore, it is not recommended for application.

To gather information on drain pipes or waste disposal pipes, watch the following construction video tutorial.

Read more

~~~~~~~~~~~~~~~~~~~~~~
Published By
Rajib Dey
www.constructioncost.co
~~~~~~~~~~~~~~~~~~~~~~

Tuesday, August 29, 2017

TMT Steel Bar – Manufacturing & Construction Basics

TMT steel bar is a steel reinforcement type that comes up with the required strength in tension, bending, shear and compression. TMT steel bar is defined as Thermo Mechanically Treated Steel that offers better ductility and malleability.
Generally, there are four types of reinforcement steels have been used in the construction – mild steel bars, deformed bars, cold twisted bars and TMT bars. Among them, TMT bars are considered to be high-quality steel bars that meet the construction requirements in terms of getting standard toughness and strength.
To understand the TMT steel bar better, you need to know the other three steel types and their application.
Mild steel bar: With a low tensile strength, mild steel bars are easy to produce and are used in allowing and manufacturing of a steel structure fabrication used in the construction work. They have low carbon and silicon level and have come up with less tensile strength than others. Their surface is plain and the round part comes up with diameter from 6 to 50mm. They can be bent easily that allows the workers to cut the rod in pieces without damage.
Deformed bars: Deformed steel bar has come up with normal ductility and has applications in residential, commercial and infrastructure fields. The common size of such steel bar stays in between 9m to 12m. The diameter of this bar varies according to their weight. The surface of the bar has lugs, ribs or deformation that provide better grip to concrete and maintains a strong bond between the two components.

Cold Twisted bars: Cold twisted bars are manufactured through a cold twisting process where bars are hardened and twisted when they stay cold. But twisting can cause surface defects on steel bars because of the occurrence torsional stress in the rebar. Torsional stress is generated by an applied torque during the twisting of an object.
TMT Bar – the basics: TMT bar goes through a metallurgical process that uses mechanical or plastic deformation process and a thermal process together. TMT stands for Thermo Mechanical Treated – the way these bars are manufactured. Mechanical deformation process includes compression or rolling, and thermal process covers heat-treatment, water quenching and cooling in a single course.
To produce TMT bars, the hot rolling process comes first that makes heated iron billets pass through the rollers of decreasing diameter. After completing the hot rolling process, the bars are water cooled by a microcontroller having a controlled quenching chamber where temperature gradient travels from the core to surface.

The bar is taken out in the air after the intense cooling process and the core area heats quenched surface layer leading to tempering the external martensite. In this process, the heat flows from the core to the outer surface adding the needed strength to the material. This unique and extensive process makes these bar high standard one with an exceptional tensile strength and ductility. It also leads the bars to achieve an excellent bonding with concrete. They are definitely corrosion resistant.
Read more

~~~~~~~~~~~~~~~~~~~~~~
Published By
Rajib Dey
www.constructioncost.co

~~~~~~~~~~~~~~~~~~~~~~

Monday, August 28, 2017

Variations among plastering & pointing

This construction video tutorial teaches you how to separate plastering and pointing on various aspects.
1.  Plaster is applied to different types brick surfaces (made with first class bricks, second class bricks, third class bricks etc).
The pointing is done for only 1st class bricks as the edges and edges of 1st class bricks are perfect.
2.  In plastering, the materials on which it is applied are disguised.
But in pointing, the materials are visible as only the joints in bricks are filled up with mortar.
3.   After plastering, the surface becomes smooth and even.
But, after pointing, the surface becomes unsmooth as only joints are covered with pointing and there may be some gapes in joints and bricks.
4.  In plastering, large quantities of materials are required as plastering is done to all surfaces of the bricks.
As pointing is done to the joints of the bricks, so, materials like cement, sand and mortar are required in less quantities.
5.  Plaster is done to the both side of the wall (inside and outside).
Pointing is done to the one side of the wall particularly to the outside of the wall.
6.  Plaster safeguards the uncovered surface of the wall from rain, heat, moisture.
In pointing, the rain, heat, moisture are consumed within the wall.
7.  In plastering lime mortar, cement mortar or lime-cement mortar are used with cement and sand.
In pointing, cement mortar and sand is applied.
8.  Plastering forms a base for employing white/color washing.
In pointing, white washing or color washing is ruled out.

9.  In plastering, defects of masonry can’t be detected.
In pointing, the masonry work is completely visible.

Read more

~~~~~~~~~~~~~~~~~~~~~~
Published By
Rajib Dey
www.constructioncost.co

~~~~~~~~~~~~~~~~~~~~~~


Details of Punching Shear in slabs and foundations

Definition of Punching Shear?
The punching shear refers to a failure system that occurs in structural members like slabs and foundation with presence of shear under the action of concentrated loads.
The action of concentrated loads remains on a minor area in the structural members. Normally, this reaction is the one from the column that behaves against the slab.
The punching shear failure mechanism can be applied in normal floor slabs, flat slabs, and in the foundation slabs underneath the column.
Punching Shear in Reinforced Concrete Slabs: The Punching shear in reinforced concrete slabs is treated as a 2D analog of the shear detected in beams. Due to unforeseen crack, this type of failure happens. It becomes difficult to control this crack by making use of main reinforcement.
Therefore, the ultimate load capacity of the structure is decreased underneath the flexural capacity with the action of shear. The punching shear is not so important with regards to beam shear.
In slabs, the punching shear happens if there are high values of concentrated loads for slabs. These load ranges from the wheel loads on the bridge slabs or the loads from over floors on the columns that support the slab floors.
Calculations in Punching Shear: If it is required to compute punching shear for the design, it is dependent on the punching shear force that is punching against the density of the slab or foundation. It can occur only if shear remains separately in the system. It becomes impossible, if any form of moment is in the pedestal or the column.
The Maximum Punching Shear Stress is obtained on the basis of the punching shear failure cone and the applied values of shear and moments. The ‘d’ denotes the effective depth of the slab. The punching shear perimeter is developed at a gapping of d/2 from the edges of the column or the pedestal. In the example given in fig 1, Dped stands for the depth of the pedestal.
1. Proper examinations should be done to ensure that the concrete is very durable.
2. If there is not sufficient strength for the concrete, verify whether the amount of supplied reinforcement is proper.
3. If it is improper, it will be better to adjust the form of the structure.
The form of the structure can be adjusted in the following ways:
1. Raise the depth of the slab
2. Expand the column size
3. Assimilation of drop panels
4. Creation of Flared column heads
5. Other foreign codes are recommended to practice other liberal designs
Different failure zones are described in the example given in figure-2 that is based together with the area where the reinforcement should be arranged. Normally vertical and traverse failure lines can be provided. It becomes difficult to identify where the failure can take place. Therefore, each prospective failure plane should have been reinforced.
Details of Punching Shear in slabs and foundations

~~~~~~~~~~~~~~~~~~~~~~
Published By
Rajib Dey
www.constructioncost.co
~~~~~~~~~~~~~~~~~~~~~~

Thursday, August 24, 2017

How beam and lintel differs as per structural behavior & load carrying system

This construction video tutorial briefly explains the variations among beam and lintel.

Both the beam and lintel are flexural as well as horizontal members and considered as the vital parts of structural system. But these differ according to their structural behavior and load carrying system.
Given below the points of differentiation:-
To gather more information, watch the following construction video

tutorial.




~~~~~~~~~~~~~~~~~~~~~~

Published By
Rajib Dey
www.constructioncost.co

~~~~~~~~~~~~~~~~~~~~~~

Wednesday, August 23, 2017

Brief overview of Moving Buildings

If the structures are shifted from its original position to new site, the process is known as moving buildings.
Moving buildings is based on the following factors:

• Motivations to move buildings
• Groundwork of structure
• Moving building method
• Types of moving buildings
• Safety measures required for moving of the structure successfully
Motivations to Move Buildings: Due to several reasons, it becomes necessary to shift buildings from its original positions to new locations. As for instance – resist demolishing of historical structures and retain them when their locations are essential for industrial purposes or as a result of increasing in population density, new residential buildings should be developed.
Another reason is that building is not built up as per exact plans and arrangements. Therefore, buildings should have been shifted to make necessary arrangements.
The process for moving building to the new position will be cost-effective as compared to demolish it and then develop new buildings.
In some cases, the residential areas are greatly affected by recurring catastrophic natural events like flooding, so, under this circumstance moving buildings will be the only alternative.
Historical houses are frequently moved and collected to build up a historical village.
Underpinning of Structure: Building underpinning plays an important role in the process of moving buildings and several methods are available through which underpinning of structure is carried out.
The Underpinning methods applied for moving buildings range from underpinning by continuous strip foundation, underpinning with piers or bases, underpinning by piles, pretest methods of underpinning, underpinning by injections, and freezing and thawing underpinning.
Moving Building Process: Generally, underpinning is the most effective method in the process of moving building. But sound knowledge and experience are required to execute such vital operation.
Usually, moving building is accomplished on the basis of sufficient surveying of the structure and calculation of loads properly as well as in-depth investigation and analysis of soils at new site of the building and at tracks on which the building is shifted, and exact jacking along with equalizing measuring strain equipment.
Moving building method comprises of the provision of a system of beams on which the building weight is retained, and these beams are arranged on a roller or wheel carriage that is set on rail track. The rail track is arranged on the ground as per the preferred direction.

To get more details, click on the following link theconstructor.org

Brief overview of Moving Buildings


~~~~~~~~~~~~~~~~~~~~~~
Published By
Rajib Dey
www.constructioncost.co
~~~~~~~~~~~~~~~~~~~~~~

Tuesday, August 22, 2017

Cross Section Analysis & Design is a powerful construction program for analysis & design of structural cross section

Cross Section Analysis & Design (most recognized software for structural uses in America, Europe, Asia and Australia) refers to a robust application that can be applied for computing an extensive range of cross section, along with the formation of design for reinforced concrete sections (rebar calculator).
The resultant cross sections are simple or composite and can comprise of one or more geometric entities (rectangles, polygons, circles, arcs etc.). With the multipurpose featured user interface, it is possible to draw the geometry of the cross section easily.

The user will be able to import standard steel sections out of a complete shape library in relation to all significant codes (AISC, Australian-New Zealand, BS, Chinese, European, Indian, Aluminum etc.)
The shape, materials or loads of a section are free from any restriction, because the program can deal with any random cross section under biaxial bending and axial loads (Mx,My,P). The program has the ability to work out all sectional properties, plot Moment – Curvature and Interaction diagrams as well as calculate the location of the neutral axis under specified sets of biaxial loads and outline the equivalent strain diagrams along with the consequential stress contours. Based on the position of the neutral axis plane on the section, these items can also be calculated.
Besides, the program is adhered to the following codes regarding reinforced concrete sections: AASHTO, UBC, AS 3600, IS 456, ACI 318, BS 8110, CSA A233, EC2, NZS 3101, CP 65.
The user will be able to produce a reinforcement design on the basis of the codes given above, outline the equivalent interaction diagrams etc., or examine a specified reinforcement pattern under the given load cases with some simple mouse clicks.
With Analysis Parameters Sets, the stress – strain curves of concrete, reinforcement and other materials are indicated parametrically. Every load case is allotted with an Analysis Parameters Set, so that estimations can be made for various design situations, like Ultimate/Serviceability or custom defined Limit States, with an automatic adjustment of the material properties, safety factors etc. As for example, while going to select the default ULS Parameters Set, the concrete curve should have been rectangular and its tensile strength should not be taken into account. Alternatively, the default SLS Parameters Set, applies a hyperbolic stress-strain curve for concrete considering its tensile strength. Here, the safety factors are automatically settled as 1.0. The user has the ability to directly modify these parameters.
An extensive material library exists along with almost all concrete/reinforcement material specifications. Besides, concrete and reinforcement materials, the user can also state custom linear, bilinear, trilinear parabolic or completely general materials.
The program supports Windows XP/Vista/7/8/8.1/10.

For more information, click on the following link engissol.com

Cross Section Analysis & Design is a powerful construction program for analysis & design of structural cross section


~~~~~~~~~~~~~~~~~~~~~~
Published By
Rajib Dey
www.constructioncost.co
~~~~~~~~~~~~~~~~~~~~~~

Monday, August 21, 2017

Some useful tips to determine the monthly rental value of your structure

From this construction video tutorial, we can gather knowledge on how to make the valuation of monthly rent concerning a building that has been developed on a land.
There are two types of rents like net rent and gross rent. Net rent does not include taxes associated with land or construction. Gross rent normally includes these types of taxes.
As for example, here, the value of plot is taken as 4,00,000 rupees (inclusive of all taxes).
The value of structure is taken as 4,70,000
As per government law, 5% of land value and 6% of construction value can be taken as return in one year.
Based on the above figure, the monthly rent of the building should be determined.
Therefore, the annual rent should be as follow :-
4,00,000 x 5% = 20,000/Rupees
Annual rent of structure = 4,70,000 x 6% = 28,200/Rupees
So, total annual rent will be = 28,200 + 20,000 = 48,200/Rupees
Therefore, monthly annual rent will be = 48,200/12 = 4017/Rupees
Now, if you want to find out the time period when total investment for land and structure will be recovered, apply the following formula :-
4,00,000 + 4,70,000 = 8,70,000/4017 = 216.58 months
To covert the value to year
216.58/12 = 18 years.

To get more information, watch the following video.

~~~~~~~~~~~~~~~~~~~~~~
Published By
Rajib Dey
www.constructioncost.co
~~~~~~~~~~~~~~~~~~~~~~

Saturday, August 19, 2017

6 helpful tips to avoid common construction delays

Construction area is a risky and high alert area. Any minor injury or accident can happen for a moment of distraction. Sometimes construction works get delayed and as a result the cost and problems create. There are many reasons of this delay; it can be happen for the communication gap, wrong planning, poor management or the unwanted raised blockers. Whatever may be the reason the result is same, the unwanted delay. This article is an overview of the problems and their solutions.

Most of the construction projects go out of control and costs back for the inability to finish the work on time. So it is important to be in schedule for maintaining the budget, but the industry is full of uncertainties so it is not possible. There are few tricks that can be used by the managers to avoid the crippling delays. The tricks are described below:


1. Minimize construction delays and blockers: The two types of problems prevent projects from finishing on time are delays and blockers. A construction delay happens generally when the things don’t go with plans; and as the construction is sometimes consecutive, it is often unavoidable. The cause of delay can be the absence of the subcontractor in the case of longer time work or delayed material shipments. Blockers are not like delays as it is a work whose completion is needful before other tasks could be completed. The best thing of avoid delaying is careful planning and the blockers should be identified at first.

2. Improve your management method:Inefficient management is another big reason for any project failure. Project managers are given the responsible to create that kind of project plan which has all the necessary elements and also deliver the completed project by the deadline. Sao the construction manager has several responsibilities and has to coordinate with the labors and materials in the job site for completing the work on time.A manager becomes great only when he can do the work before time with the problems and blockers.

3. Plan, plan, plan:A great project plan can be done when the project manager is always updated with the planning and enable quickly diagnose potential challenges and solve problem instantly before any delay. Many contractors start their projects without clear timeline or prior communication etc. and it is a big mistake. The project should always contain with the details and variables to avoid the delays. A successful plan always has unforeseen circumstances, clear guideline to finish it in right time. The software like eSUB or other software options can maintain the project planning.

4. Assign clear roles and responsibilities:The commercial construction projects have contractors, employees, subcontractors, managers and other peoples. And for any kind of failure, each party is equally responsible. Avoiding critical tasks lead the projects in delay. By establishing roles, responsibilities and focusing on the goal, the unwanted delays can be avoided. To get buy-in from everyone before beginning any project plan is essential. By talking with all the key players in a project, the involvement of the members in the project can be seen.

5. Schedule contractors far in advance:Two co creators of HGTV’s hit TV-show Property Brothers, Drew and Jonathan Scott have launched a venture called Dream Homes that addresses the problem about the timing for settle down a new project. Bridget McMullin of McMullin Design Group also warned that the contractors, designers and architects often delayed their work for the setting of the first meeting. To avoid delays and costs, you need to determine the time and the contractors. To complete all the process from arranging meeting to choosing contactors and making schedules, you need 3 months. So it is always better to be active in doing this entire works.

6. Establish clear communication between parties: The poor communications between two parties can turn the little problems into big delays. In the certain created challenges it becomes crucial to contact directly between the contractors and project management team. So as a contractor you must quickly diagnose asses and communicate with all eth members to make a solution. A guide of timely project completion by Design Blendz shows the benefits of good communications. The active participation of all the employees makes any project successful and completed in time.

Though the construction project management software has made it easier than earlier to deliver the right updates from the site to all the key stakeholders but this should be maintained properly. This practice can bring everyone in the same page and the production of work can be done faster.


For more information please follow the link: blog.capterra.com

6 helpful tips to avoid common construction delays


~~~~~~~~~~~~~~~~~~~~~~~~
Published By
Rajib Dey
www.constructioncost.co
~~~~~~~~~~~~~~~~~~~~~~~~

Friday, August 18, 2017

Safety Measures in Construction Site

Constructions sites are the place where risks are inevitable. The workers on the job site are exposed to various dangerous situations. Even a single miss of safety term can cause severe injuries, sometimes death. So, it is important to follow the safety tools to avoid life threatening problems. The effect of simple safety policy will bring in a calm and friendly working environment for the workers.
Following a safety precaution not only protects the workers from fatal consequences but also keeps builders away from legal issues raised because of the infringement in the safety term. The content discusses the basic site safety rules that every work site must follow. They are a simple set of rules offering results rooted deep in a problem free construction environment.
• The site manager must conduct a site meeting before the construction process starts. It should be attained by the entire work force, and the possible safety problems of the job site should be discussed to solve the existing problems.

• The site manager must conduct a site meeting before the construction process starts. It should be attained by the entire work force, and the possible safety problems of the job site should be discussed to solve the existing problems.
• The workers must keep the job site tidy, keeping aside the dangerous items that cause potential risks. The demolished materials like mortar, glass, hardcore and concrete should be dumped away from the working area. If it is not possible, they should be separated using fences.
• Every worker must put on the necessary safety protections to keep themselves unaffected if the worse situation comes. You must be accompanied by hard hats, gloves, heavy boots, and protection glasses during your work.
• Using right tool and machinery also comes under the building site safety policies. The machines should be in a working condition and must be maintained in a good way.
• Working at heights is another thing that is common in the construction field. Risks are also higher for those who are working above the usual height. To avoid risk related to fall, site instructor should check ladders and scaffolding prior to the job. Safety harness is another best option to ignore the problems related to working at heights.
• Banning on alcohol consumption on the job site is the rule strictly followed by the workers.
• Workers should be informed about the health problems caused by a prolonged work in hot, cold and wet environments. They cause a range of health risks, from dehydration to sun strokes.
• Every job site keeps the First Aid materials in an organized way that can avert any kind of inconvenience.
• Every worker must have clear knowledge of what to do if an emergency strikes. The work responsibility must be divided among workers so that they can take quick action to cut down the damages.
Maintaining a proper safety protocol is one of the important things in a construction work. Every building site must follow the rules as strictly as they are mentioned in the rule book. The infringement in the safety term can bring unnecessary legal issues and halt the construction work temporarily or permanently. The risk of life is the major thing to be concerned.
To get more information, click on the following link civilengineerlink.com
Safety Measures in Construction Site

~~~~~~~~~~~~~~~~~~~~~~~~
Published By
Rajib Dey
www.constructioncost.co
~~~~~~~~~~~~~~~~~~~~~~~~

Thursday, August 17, 2017

Benefits of drones in construction

Drones are rapidly changing the industry scenario, especially in the fields of civil engineering and surveying. They are reaching the odd locations that are untouched by the human resource. The application of this technology, though, goes beyond these two names. They are strongly imprinting their values across the industry, from real estate to golfing. The achievements earned by this technology are countless, and they deal with toughest challenges with ease and bring out the productive result for the companies. The content explains in brief how they earned this unmatched reputation in the dynamic world.
Observation:
Navigating the difficult location in the construction field is no longer a tricky job. Unmanned Aerial Vehicles are performing the job as skillfully as no one can do. It sends images of what it observes to the planning team.
The data sent by drones contain impressive details of the objects, including the smallest option. The 360 degree panorama views help civil engineers divide the work as per the priority basis. Operators also share these images in order to come up with a better plan. The data solve various complex issues like project timing, equipment needs and prevailing challenges of a construction.
Surveying:
Drones play major roles for surveying. They quite satisfyingly assist Geographical Information System (GIS) professionals. GIS is known for their services like locating boundaries of the property, subdividing land and surveying construction sites. No doubt to say, drones have already made loud noises for catering the same functions proficiently and flawlessly. They send still images of a construction map to a cloud-based storage from where authorities can access and assess the data to plan meticulously. Since the cameras and the distance can be regulated remotely, they rise above than natural and artificial obstacles.
Costing:
Drones are affordable and accurate, and this is why they are entering the industry at large. The benefits are countless and at the same time reliable. They accelerate the production, assess the present situation and help in figuring out the problem more efficiently than any other does. Traditionally, construction has been the manpower controlled field. With the introduction of this technology, the age-old thought starts getting obsolete. They use the human – resource team in a profitable way and cut down the unnecessary expenses.
Drones have already made their presence felt in the industry with offering profits more than expected. Getting real time data of the construction has become easier. Thus, it also solves many difficult challenges prevailing over the field.
However, there exist regulations, probable risks and service options to take into consideration prior to launch a drone program.
To get more information, click on the following link computerworld.com/

Various types of tests conducted to verify the quality of aggregates in road work


~~~~~~~~~~~~~~~~~~~~~~~~
Published By
Rajib Dey
www.constructioncost.co
~~~~~~~~~~~~~~~~~~~~~~~~


Wednesday, August 16, 2017

Various types of tests conducted to verify the quality of aggregates in road work

Aggregate is a vital element in pavement construction. The load transfer capacity of pavements is significantly impacted by the aggregated. So, it is recommended to examine the aggregates comprehensively prior to utilize them in the construction site.
The aggregates should contain the properties like durable and long-lasting with perfect shape and size so that the pavement can function monolithically. Aggregates are evaluated for strength, toughness, solidity, shape, and water absorption.
In order to decide the suitability of the aggregate for use in pavement construction, The following tests are conducted to check whether the aggregates are suitable to be utilized in pavement construction:

In order to decide the suitability of the aggregate for use in pavement construction, The following tests are conducted to check whether the aggregates are suitable to be utilized in pavement construction:
1.CRUSHING TEST: Crushing under compressive stress is a model to check the eligibility of pavement material for getting passed or failed. A test is organized with IS: 2386 part-IV and applied to find out the crushing strength of aggregates. The aggregate crushing value offers a relevant measure of resistance to crushing under increasingly employed crushing load.
2.ABRASION TEST: Abrasion test is accomplished to examine the rigidity of aggregates as well as determine whether they can be used for various pavement construction works. Los Angeles abrasion test is mostly suitable for executing the hardness property and it is implemented in India (IS: 2386 part-IV).
3.IMPACT TEST: The aggregate impact test is accomplished to verify the resistance to impact of aggregates. Aggregates which have passed 12.5 mm sieve and conserved on 10 mm sieve is filled with a cylindrical steel cup having internal dia 10.2 mm and depth 5 cm that is connected to a metal base of impact testing machine. The material is covered with 3 layers where each layer is tamped for 25 numbers of blows. Metal hammer having weight 13.5 to 14 Kg is set to drop with a free fall of 38.0 cm through vertical guides and the test specimen is dependent on 15 numbers of blows.
4.SOUNDNESS TEST: Soundness test is conducted to analyze the resistance of aggregates against weathering action, by carrying out accelerated weathering test cycles. The Porous aggregates is dependent on freezing and thawing is liable to decompose beforehand. To determine the stability of such aggregates, they are dependent on a faster soundness test as stated in IS: 2386 part-V.
5.SHAPE TESTS: The particle shape of the aggregate mass is set with the proportion of rough and enlarged particles in it. Large and enlarged aggregates may be damaged to higher workability and stability of mixes.
6.SPECIFIC GRAVITY AND WATER ABSORPTION: The design of concrete and bituminous mixes is mostly based on the properties like specific gravity and water absorption of aggregates. The specific gravity of a solid refers to the proportion of its mass to that of an equivalent volume of distilled water at an indicated temperature. As the aggregates may include water-permeable voids, so the following two measures of specific gravity of aggregates are utilized:
1. Apparent specific gravity and
2. Bulk specific gravity.
7.BITUMEN ADHESION TEST: Bitumen is compatible with all general types of road aggregates on condition that they are dry and do not contain dust. Without water, no adhesion issue of bituminous construction occurs.
If the aggregate is wet and cold, the adhesion issue may happen. This issue can be handled by eliminating moisture from the aggregate by drying and raising the mixing temperature. Besides, the existence of water leads to removal of binder from the coated aggregates. This problem happens if bitumen mixture is absorbent to water.
To get more information, click on the following link civilblog.org/
Various types of tests conducted to verify the quality of aggregates in road work

~~~~~~~~~~~~~~~~~~~~~~~~
PUBLISHED BY
RAJIB DEY
WWW.CONSTRUCTIONCOST.CO
~~~~~~~~~~~~~~~~~~~~~~~~